I wonder how much of this is Instagram stealing Snapchat's userbase and how much is it simply converting its existing userbase over to using Snapchat's new inno

I wonder how much of this is Instagram stealing Snapchat's userbase and how much is it simply converting its existing userbase over to using Snapchat's new innovative features. If Instagram has more users than Snapchat, saying "Instagram's Snapchat feature has more users than Snapchat" isn't really as significant as it sounds, and doesn't necessarily represent any erosion of their userbase or threaten their growth. Of course their userbases are not mutually exclusive, but I do get the impression there's a rough demographic separation.